Maternal age and diabetes in childhood

Two recent meta-analyses of early life influences on the risk of early onset type 1 diabetes largely confirm what previous studies have shown.1 2 The first found that childhood onset diabetes is associated with increasing birth weight, equivalent to a 7% increase in risk for every 1000 g in weight,1 and the second reported that caesarean section increases the risk by around 20%.2 A third more recent pooled analysis of five cohort studies and 25 case-control studies provides formal confirmation that the risk of childhood onset diabetes increases with maternal age: 5% for each five years of age.3 The studies included were heterogeneous, so interpreting the results is a challenge.

Why should the age of the mother at delivery influence the risk of diabetes in the child? There is much speculation, but the main explanations are that biological programming of the child is in some way affected by the age of the mother, or perhaps the father, and that the difference is caused by environmental or …